1. Field of the Invention
The present invention relates to improved construction techniques and rotary drive mechanisms for multiple photograph display boxes.
2. Description of the Prior Art
Prior types of card index device are of general interest only since they are most often characterized by the fact that only one side of the card need be displayed after indexing. An early U.S. Pat. No. 1,813,442 discloses a mechanized rotary-type sign display which includes the two fields of view, i.e., the front of the top card is displayed simultaneously with the backside of the bottom card. U.S. Pat. No. 1,126,814 discloses another form of picture display device wherein rotary cartridges each containing a number of pictures are selectively displayed.
U.S. Pat. No. 978,162 discloses yet another form of picture exhibiting apparatus wherein the multiple of pictures is rotated in a horizontal plane about a vertical axis. The U.S. Pat. No. 3,218,743 discloses a picture exhibiting apparatus that uses an album-type collection of individual photographs wherein each album can be inserted in the display device for subsequent individual viewing of the pictures. European patent application No. 82104601.8 is of particular interest in that it teaches a rotary menu card holder for use in a microwave oven wherein both backside and frontside of the cards are presented for view as the device is flipped over.